In 2010, 32.4% of adults in the United States who had seen a physician or other health care professional in the past year had received a recommendation to begin or continue to do exercise or physical activity, up from 22.6% in 2000. At each time point, women were more likely than men to have been advised to exercise.

Between 2000 and 2010 the percentage of patients aged 85 and older who received a “get fit” recommendation from a physician nearly doubled from 15.3% to 28.9%. The percentage of patients aged 18-24 years receiving such a recommendation also increased during the same time period, but to a lesser extent (from 10.4% to 16.1%).

The report also found that the percentage of adults with hypertension, cardiovascular disease, cancer, and diabetes who received exercise advice from a physician increased between 2000 and 2010.

“Trends over the past 10 years suggest that the medical community is increasing its efforts to recommend participation in exercise and other physical activity that research has shown to be associated with substantial health benefits,” the report states. “Still, the prevalence of receiving this advice remains well below one-half of U.S. adults and varies substantially across population subgroups.”

Renal denervation may be the next big thing in endovascular intervention, and not just because of the many patients it might help.

Renal denervation is a new procedure for lowering blood pressure that involves placing a radiofrequency catheter inside both of a patient’s renal arteries and zapping the tissue four to eight times on each side, gently enough not to cause trauma but firmly enough to damage the renal nerves and block sympathetic activity and the kidneys’ renin release. It remains investigational in the United States, where a 500-patient pivotal trial recently started, but it’s been available on a routine basis in Europe since 2010, and according to Horst Sievert, a German interventional cardiologist who’s done many denervations since then, it’s been taking off both in terms of the number of endovascular physicians offering it and the number of patients with drug-resistant hypertension being treated.

image courtesy Wikimedia Commons

Though still off the U.S. market, the prospect of FDA approval within the next couple of years was enough to win renal denervation a special session at ISET 2012 last week in Miami Beach. My news article on those talks is here.

An apparently safe, relatively easy, 60-minute procedure that can durably cut systolic blood pressure by about 30 mm Hg in patients who remain hypertensive despite treatment with multiple drugs is certainly very attractive. It may be even more appealing if early evidence pans out and the treatment also helps normalize glycemic control and reduce hyperinsulinemia in at least some patients.

But when vascular medicine specialist Michael Jaff said at the meeting that renal denervation “could arguably be the most exciting advance in interventional vascular medicine,” and that “in the near term I’m incredibly bullish,” it was hard not to imagine that it was more than optimized patient care that made his pulse quicken.

Endovascular medicine became a medical growth industry more than 30 years ago, when it started to become a routine part of cardiology, a way to less-invasively treat stenotic coronary arteries. Since then, it’s become a major part of all vascular medicine, but in recent years the coronary part showed a definite leveling off. Just last year in a talk at ISET, Martin Leon, one of the world’s foremost interventional cardiologists, declared that endovascular coronary interventions appeared to have reached a volume plateau that would not change anytime soon. He said his early recognition of this trend was a motivation for him to turn his attention to transcatheter aortic valve replacement, which has now emerged as a new way for interventional cardiologists to ply their trade.

Renal denervation may be the next step along the same path. If the pivotal trial results and further clinical experience confirm the early findings of safety and efficacy, and especially if the very early findings of a beneficial glycemic effect also pan out, it may well fulfill Dr. Sievert’s prediction that “renal denervation will become as important as percutaneous coronary intervention.”

Important not just for patients, but for practitioners too. Busy hands are happy hands.

A recent Scientific American article calling for an end to “the war on salt” rips long-standing medical concerns about high-sodium diets, citing for support a 2011 meta-analysis of seven studies published in the American Journal of Hypertension and a 2011 observational study in JAMA, among other background. If the U.S. does “conquer salt,” all we are sure to gain is “bland french fries,” the Scientific American writer believes.

Salt crystals photo by Mark Schellhase (Wikimedia Commons).

That view is opposed by a legion of professional health organizations recommending dietary sodium reductions, including the American Heart Association, the American Society of Hypertension, the American Medical Association, the American Public Health Association, the National Academy of Sciences, the National Research Council, the Pan American Health Organization, the World Health Organization, and the World Hypertension League. Not to mention the governments of the United States, Canada, European Union, United Kingdom, Ireland, Finland, Australia, and New Zealand.

What’s going on here? Are all these medical organizations and countries disregarding the data?

Hardly, Dr. Lawrence J. Appel said at the 2011 scientific congress of the American Diabetes Association. Dr. Appel, who chaired the salt committee for the U.S. Dietary Guidelines for Americans, 2010, summarized the extensive medical literature on the effects of sodium intake and reduction of sodium intake. You can find a similar summary in a 2011 “call to action” in an American Heart Association Presidential Advisory, “The Importance of Population-wide Sodium Reduction as a Means to Prevent Cardiovascular Disease and Stroke,” for which Dr. Appel was the lead author.

“If you reduced sodium ingestion by 1,200 mg per day, which is roughly 1/3 of average intake, you would reduce the number of heart attacks by an estimated 100,000 per year. Interestingly, that’s what you get with drug therapy for hypertension, or if you got 50% of people who smoke to stop,” said Dr. Appel, professor of medicine at Johns Hopkins University, where he is chair of the Welch Center for Prevention, Epidemiology and Clinic Research.

And since the Scientific American article appeared, a study in the Archives of Internal Medicine by the U.S. Centers for Disease Control and Prevention reported a 20% increase in risk for all-cause mortality with higher sodium intake in the general U.S. population.

So, is the “controversy” just a case of sometimes conflicting data? Is there something fueling this besides data?

In 2010, the Institute of Medicine recommended regulating the levels of sodium that manufacturers put into products. In the United States, 77% of the sodium in our diet comes from processed foods. More than half the total U.S. population and the majority of U.S. adults fit into categories of people who are at higher risk for adverse health consequences of high-sodium diets (including anyone older than 50 years; African-Americans ages 2 and up, and anyone age 2 or older with high blood pressure, diabetes or chronic kidney disease).

That strategy has been stymied by “a counteroffensive that is fueled by commercial interests” such as the Salt Institute, with support from a handful of scientists, Dr. Appel said.

Photo by Garitzko (Wikimedia Commons).

He spoke before the Scientific American article appeared, but some of the comments on the article’s website seem to back him up. For example, the article repeatedly cites a skeptic of sodium-reduction strategies, Dr. Michael H. Alderman, professor emeritus of epidemiology at Albert Einstein College of Medicine. But the article doesn’t mentioning that Dr. Alderman has been a paid consultant to the Salt Institute and failed to disclose that conflict of interest in journal articles, one commentator noted.

For the record, Dr. Appel disclosed having no conflicts of interest in his talk at the American Diabetes Association.

Critics of regulating dietary sodium make three arguments that sometimes get major press attention, Dr. Appel said. The first is that nothing should be done until we have a large, controlled clinical trial of the effects of sodium reduction. “Such trials are almost impossible because of logistical, financial and ethical considerations,” he counters. The second argument suggests that only “salt sensitive” persons should reduce their salt intake, but there is no test to tell whether an individual is salt sensitive and the scope of the hypertension epidemic makes this argument irrelevant, Dr. Appel said. Lastly, some claim that sodium reduction might be harmful, which is “a myth based on cohort studies with methodological flaws and over-interpretation of biomarker data,” he said.

So if you or your patients hear cries in the media about an unfair war on salt, here’s my suggestion: Take it with a grain of salt.

Tuesday morning I sat through the late-breaker session at the annual meeting of the American Society of Hypertension. The last two oral abstracts were based on work from the International Consortium for Blood Pressure Genome-wide Association Studies (GWAS), whose goal is to identify genetic variants in known and novel genes that influence blood pressure in the general population. In the first talk, Dr. Mark Caulfield discussed the consortium’s methodology and the indentification of 29 single nucleotide polymorphisms (SNPs) associated with blood pressure — 16 of which were at novel loci.

In the second talk, Dr. Daniel Levy discussed the development of a genetic risk score that incorporated all 29 alleles identified in the GWA and the score’s associations with several blood pressure-related clinical outcomes (such as target organ damage and cardiovascular events). Before doing so though, he asked everyone in the audience to refrain from photographing the slides or recording the presentation due to an upcoming publication of the study.

As a reporter, I don’t consider myself bound by such requests for secrecy. If it’s presented in a public forum, it’s fair game in my book.

My question is to physicians, many of whom are now quite well-published themselves, thanks to everyman’s news outlets — blogs and social media. Would you refrain from discussing the study in a widely-read (or completely unknown) blog or online forum? Are you going to scoop reporters, who comply with the request? Do you think that such requests slow medical research?

It might be an unfair overgeneralization to say that insurance companies make people sick, but a study presented at the annual meeting of the American Society for Metabolic & Bariatric Surgery looking into the consequences of morbidly obese patients who were denied coverage for bariatric surgery confirms that, in this population, insurers often stand in the way of helping people get well.

Image via Flickr user Leoncillo Sabino by Creative Commons License

Dr. Ayman B. Al Harakeh and colleagues at Gundersen Lutheran Medical Foundation in LaCrosse, Wis., compared the natural history and metabolic consequences of morbid obesity for patients who were denied bariatric surgery (despite satisfying NIH criteria and being deemed appropriate candidates) to that of patients who underwent laparoscopic Roux-en-Y Gastric Bypass at their institution from 2001-2007. Compared with the 587 patients in the LRYGB cohort, the 189 patients in the denials cohort were significantly more likely to develop new comorbidities, including diabetes, hypertension, obstructive sleep apnea, lipid disorders, and gastroesophageal reflux disease within a 3-year follow-up period, despite no change in BMI.

Because the data for the study were collected retrospectively through a medical record review, the specific reasons for the insurance denials were not available, according to Dr. Al Harakeh, who nonetheless lamented insurance companies’ apparent ability to deny bariatric surgery arbitrarily: “Often, they just don’t want patients to have the surgery because of the high economic impact. We see that happen all the time.”

The findings indicate “a clear and present danger to at-risk obese patients,” according to discussant Dr. John Morton, director of bariatric surgery and surgical quality at Stanford Hospital and Clinics in Palo Alto, Cal., who stressed the need to investigate and, when appropriate, fight the insurance denials.

The specter of a blood pressure J curve arose again last week at the ACC meeting in an analysis of 5,000 patients with diabetes and coronary artery disease in the INVEST trial, who showed a clear, increased rate of death when their antihypertensive treatment dropped their systolic blood pressure below 115 mm Hg (see photo)

One of the best recent analyses to show evidence for the J curve was a 2006 report that used data collected in that same 22,000-patient INVEST study, although the older analysis used data from all patients, not just the ones with diabetes, and focused on the link between low diastolic pressure and both death and myocardial infarction. The 2006 report said that patients faced risk when their diastolic pressure fell below 70 mm Hg.

The reason why excessively low pressure can be deadly isn’t clear, but possible explanations include low blood flow to critical organs such as the kidney and brain, or that low pressures are markers for patients with severe underlying illness or advanced vascular disease. These mechanisms probably depend more on low diastolic pressure, but, of course, when systolic pressure is low diastolic usually is too.

Whatever the reason, the finding is a reminder that it’s important for physicians to focus not on simply getting a patient’s blood pressure low, but on getting it within a target range. As one INVEST collaborator told me, “My guess is that on follow-up patients were lower, but their physicians made no adjustment [in their antihypertensive dosages] unless the patients complained of symptoms.”

It’s tempting to speculate that results of the ACCORD blood pressure trial, also reported at the ACC meeting–which showed that getting patients with diabetes to an average systolic pressure of 119 mm Hg led to no better outcome than in patients kept at an average of 133 mm Hg–occurred not because a systolic pressure of 133 mm Hg is ideal but because too many patients in the tight-control group had systolic and diastolic pressures that ran below 115/70 mm Hg. It’s quite possible that the detrimental effects of excessively low pressures masked the benefit from systolic pressures in the 120-130 mm Hg range.

My full report on the ACCORD blood pressure and INVEST studies at the ACC meeting is here.

Rear Admiral Penelope Slade-Sawyer updated attendees on Healthy People 2010, acknowledging straightaway that the health initiative did not meet its two core goals of eliminating health disparities and improving the quality and years of healthy living for Americans.

Strides were made in reducing coronary heart disease death rates and in cholesterol screening, but efforts fell short in terms of blood pressure monitoring, participation in physical activity, and decreasing the percentage of overweight and obese Americans.

Audience members asked whether Healthy People intervenes or simply sets goals, to which Rear Adm. Slade-Sawyer said the 10-year initiative includes education and advocacy in addition to goal setting.

One member of the audience wanted government officials to put more teeth in their efforts, suggesting taxes be levied against those pushing foods containing horrific sodium levels. Consider that Burger King’s original Whopper with cheese has a stunning 1,450 mg of sodium, while Applebee’s quesadilla burger comes in at 559 mg .

As a native Chicagoan, I got a little nervous about such talk, recalling my fearless leaders recent ban on the sale of foie gras based on animal cruelty concerns. The ban was later repealed with the help of Mayor Richard Daley, who claimed the ban made Chicago an international laughing stock.

Flickr user bloggyboulga

But in a subsequent session, I was stopped in my tracks by a simple statistic – no doubt widely known by most of the physicians in attendance. Roughly 43% of black Americans over the age of 20 years (not a typo) have hypertension, a particularly powerful risk factor for cardiovascular disease.

Image courtesy of Flickr user daystar297 via Creative Commons

Safeguarding the next generation from salt suddenly didn’t look all that ludicrous.